The Old Improbable Island Wiki

The Madness duck is the undisputed leader of all the insane birds¹⁾ in the jungle. ²⁾³⁾ He is also looked up to as a beacon of the good old ways, and a steadfast role model, by many of the more insane monsters in the jungle. The Madness duck is:

blue. Except when it's not.
mad.⁴⁾
prone to going QUACK a lot, in a mildly hysterical manner. and then staring at you.⁵⁾⁶⁾
lethal, even in small doses. Say NO to ducks, kids.

In short, the lesson that all⁷⁾ contestants take from their meetings with the Duck is: if it looks like a duck, and QUACKS like a duck, chances are, you should run like hell.

The madness duck is one of the reasons Cousjava considers himself mad. That is, Cousjava says that the madness duck says he's mad, so he must be mad.⁸⁾

¹⁾

Not to be confused with the mental birds

²⁾

except for the mighty magpie.

³⁾

and sometimes Shi, depending on her mood

⁴⁾

though by island standards this is perhaps its least remarkable trait.

⁵⁾

If it quacks three times, it's a different duck altogether

⁶⁾

An altogether more dangerous duck, even!

⁷⁾

except those who are now sitting in the failboat, or dead

⁸⁾

What, you think you're mad just because the madness duck tells you you are? You must be mad.